Snort rule matching denial of service
| snort-rule-matching-dos (31430) |  Low Risk |
Description:
Snort is vulnerable to a denial of service caused by a vulnerability in the rule matching algorithm. A remote attacker could send a specially-crafted packet to cause the rule matching algorithm to consume resources and cause a decreased packet detection rate or a denial of service.
Platforms Affected:
- Gentoo, Linux
- MandrakeSoft, Mandrake Linux 2006 X86_64
- MandrakeSoft, Mandrake Linux 2006
- MandrakeSoft, Mandrake Linux 2007
- MandrakeSoft, Mandrake Linux 2007 X86_64
- MandrakeSoft, Mandrake Linux Corporate Server 4.0 X86_64
- MandrakeSoft, Mandrake Linux Corporate Server 4.0
- MandrakeSoft, Mandrake Multi Network Firewall 2.0
- Snort, Snort 2.4.3
Remedy:
Upgrade to the latest version of Snort (2.6.1.2 or later), available from the Snort Web site. See References.
For Gentoo Linux:
Refer to GLSA 200702-03 for patch, upgrade, or suggested workaround information. See References.
For Mandriva Linux (snort):
Refer to MDKSA-2007:051 for patch, upgrade, or suggested workaround information. See References.
For other distributions:
Contact your vendor for upgrade or patch information.
Consequences:
Denial of Service
References:
- Snort Web site, Snort.org at http://www.snort.org/.
- BID-21991: Snort Backtracking Denial of Service Vulnerability
- CVE-2006-6931: Algorithmic complexity vulnerability in Snort before 2.6.1, during predicate evaluation in rule matching for certain rules, allows remote attackers to cause a denial of service (CPU consumption and detection outage) via crafted network traffic, aka a backtracking attack.
- GLSA-200702-03: Snort: Denial of Service
- MDKSA-2007:051: Updated snort packages fix DoS vulnerability
- OSVDB ID: 32096: Snort Rule Predicate Rule Matching Backtrack DoS
- SA23716: Snort Rule Matching Backtrack Denial of Service Vulnerability
- SECTRACK ID: 1017508: Snort Rule Matching Complexity Lets Remote Users Deny Service via Backtracking Attacks
Reported:
Jan 11, 2007
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